Surtsey - General information GENERAL INFORMATION The Surtsey Eruption 1963-1967 The Surtsey eruption is among the longest eruptions to have occurred in Iceland in historical times. The first sign of an eruption came early in the morning of November 14, 1963, at a site approximately 18 km southwest of Heimaey, the largest of the Vestmannaeyjar (Westman Islands). The eruption is believed to have commenced a few days earlier on the sea floor, at a depth of 130 m. Explosive phases characterized the Surtsey eruption in the beginning, and due to the rapid cooling effects of the sea, the hot magma transformed into tephra (volcanic ash). The tephra production was tremendous, and an island had already been formed the day after – on November 15. By the end of January 1964, the new island’s elevation was 174 m, or over 300 m above the sea floor where it had all begun.

The eruption activity moved to the northwest on February 1, 1964, where tephra erupted from young Surtur (Surtungur) until the beginning of April. From December 28, 1963, to January 6, 1964, a submarine eruption was evident in a location approximately 2.5 km east-northeast of Surtsey. A ridge some 100 m high formed on the sea floor. It was given the name Surtla but never grew to become an island, as did Surtsey. On April 4, 1964, a lava eruption commenced in the western crater on Surtsey. The lava flowed mainly to the south and east and formed a broad lava shield that was, in the end, 100 m thick at the crater. On May 17, 1964, the lava eruption from this crater ceased. By that time Surtsey had grown in area to 2.4 km².

At the end of May 1965, a new eruption seemed to be taking place at the bottom of the ocean 0.6 km east-northeast of Surtsey, and on May 28 an island could be seen. This island was called Syrtlingur, and explosion eruptions occurred there until the beginning of October 1965. Syrtlingur reached a maximum area of 0.15 km², but it did not remain in existence for long. The tiny island was quickly broken down by the ocean and had disappeared completely by October 24, 1965. Another small island, Jólnir, was formed during Christmas 1965, in an eruption on the sea floor 0.9 km to the southwest of Surtsey. This island was in many respects very similar to Syrtlingur. It was about 70 m high and reached an area of approximately 0.3 km². Jólnir was seen to erupt for the last time on August 10, 1966, and it had disappeared into the depths of the sea by the end of October that same year.

On August 19, 1966, a lava eruption began anew on Surtsey, this time from new craters in the eastern tephra crater; i.e., in old Surtur. Lava flowed from these craters to the east and southeast until the beginning of June 1967, when the Surtsey eruption ceased. From December 1966 until January 1967 there were also eruptions in five different locations in the eastern tephra crater, but lava flow was limited. When the eruptions had come to an end in June 1967, they had lasted for over three and a half year. The area of the island was 2.7 km² at this time. A total of 1.1 km³ of volcanic products arose from the Surtsey eruption, of which 60-70% were tephra and 30-40% lava. In many respects the Surtsey eruption is comparable to eruptions that led to the formation of hyaloclastite (palagonite) mountains in Iceland during the Ice Age. Similarities have been observed between Surtsey and table mountains (tuyas).

After witnessing the Surtsey eruption, scientists have argued that the Vestmannaeyjar, with the exception of the northernmost part of Heimaey, were formed in similar submarine eruptions as Surtsey. The core of Surtsey is variably coarse tephra that was formed in explosive eruptions. Above sea level the tephra formed two crescent-shaped craters in the centre of the island. The base of the lava in Surtsey is, to a large extent, made of breccia, which was formed by rapid cooling and marine erosion as the lava flowed into the sea. The eruptions occurred in a total of eight locations on the island. It then follows that under the surface is a net of dikes by which the lava was brought to the surface. A small ness was formed on the northernmost part of Surtsey. This is a coastal formation that receives material from the lava fields broken down by the ocean on the southern part of the island. The prevailing wind directions ensure that the eroded material is deposited on the northern leeside of the island. (author: Sveinn P.

Jakobsson – sjak@ni.is ) - last updated 06-May-2007 Today in science: An island is born | Earth | EarthSky Today in science: An island is born By Deborah Byrd in Earth | November 14, 2016 On November 14 1963, crew aboard a trawler sailing near Iceland spotted a column of smoke rising from the sea surface. A new island, Surtsey, was being born. View larger. | The new-born island of Surtsey, off the coast of Iceland, on November 30, 1963. Howell Williams captured this photo 16 days after the eruption that created Surtsey began. Image via NOAA. November 14 1963. On this date, a cook aboard a trawler called Ísleifur II – sailing south of Iceland – spotted a column of dark smoke rising from the surface of the sea. The ship’s captain thought it be a boat on fire and turned his vessel to investigate. What they found was an island in the process of being born: explosive volcanic eruptions originating from below the sea surface, belching black columns of ash.

The new island was later named Surtsey, for Surtur, a fire jötunn (a mythological race of Norse giants). The eruption continued for several years. After just a few days, the new island measured over 500 meters (1,640 feet) in length and had reached a height of 45 meters (147 feet). And it continued to grow. By April of 1965, ash had blocked sea water from the crater area. Lava flows became prominent, forming a hard cap of solid rocks over the lower slopes of the new island. This prevented the waves from washing away the island. The eruption ultimately lasted three-and-a-half years, ending in June 1967. New island off the coast of Pakistan, one day after it emerged from the waves on September 24, 2013. Image via BBC World News Facebook . Surtsey is only the most famous, or one of the most famous, of the islands known to have emerged from below the sea surface in living memory. For example, on September 24, 2013, an earthquake caused the birth of a new mud island off Pakistan’s southern coast.

Another famous example from the 20th century is Anak Krakatau (“child of Krakatoa”), which formed in the flooded caldera of that Indonesian volcano in 1930. Fun Facts about Volcanoes in Iceland - Bungalo Fun Facts about Volcanoes in Iceland 2 minute readby Catharine Fulton 54 Facebook Twitter Remember when Eyjafjallajökull swept into popular culture with its massive ash cloud in 2010 and won everybody’s hearts? Well, maybe not ‘won hearts’, per se… more like ‘enrage everybody that has a flight booked and had to sit tight while some unpronounceable volcano spewed ash all over the place.’ Well, another Icelandic volcano is in the news these days on account of a non-stop swarm of earthquakes under Vatnajökull glacier over the past few days, though it hasn’t erupted yet. Pro tip: This volcano is way in the middle of the country, far from Reykjavík and other towns. So you can still head over to your Icelandic summerhouse and rest easy .

The volcano is called Bárðarbunga, and in honour of its 15-minutes of fame, here are some fun facts about Bárðarbunga and volcanism in Iceland: #1 — Pronounciation Bárðarbunga is pronounced BOWR-thar-boon-ga. Say it with me now: Bárðarbunga. Well done! #2 — Meaning How to put this… it means ‘Bárðar’s bulge’. This Bárðar fellow must have been a particularly proud young viking to name the country’s second largest mountain after his — ahem — manhood. #3 — Location Bárðarbunga is located at the north-west corner of Vatnajökull, Europe’s largest glacier. In fact, it’s covered with over a kilometre of ice! Due to this frosty cap, flooding would be a definite result of an eruption. #4 — A Volcanic Island Iceland is home to 30 active volcano systems, though only a lucky 13 of those have erupted since the country was founded in the year 874.

The number of active volcanoes has to do with Iceland’s position straddling the North American and Eurasian tectonic plates. In Iceland, you can even snorkel or scuba dive between the continental plates in Silfra . It’s gorgeous! Image Credit: Wikipedia #5 — Earthquakes While the seismic activity around Bárðarbunga has resulted in around 1700 earthquakes in the country since Saturday morning, even on days when the country isn’t on #volcanowatch the earth is still always shaking. You can blame this one on those tectonic plates again. There are a at least a couple of earthquakes happening in Iceland every day. Every now and then you may even feel one in Reykjavík ! #6 — Surtsey A volcanic eruption off the coast of Iceland formed a whole new island in 1963. The underwater eruption that formed the island Surtsey, began on 14 November 1963 and continued until 5 June 1967. The island was declared a nature reserve while the eruption was still happening and is off-limits to all people (except the odd researcher) in order to preserve the natural evolution of plant and animal life on the land.

Crazy! Image Credit: Wikipedia No eruption has begun and these things can’t really be predicted with any degree of accuracy. Bárðarbunga may just be dancing for us right now. I mean, who doesn’t like a dance party? Do you have total volcano fever right now? Regardless, why don’t you drop us a line on Facebook just to say ‘hi’. 54 Volcanic island | Article about Volcanic island by The Free Dictionary Volcanic island | Article about Volcanic island by The Free Dictionary Also found in: Dictionary , Thesaurus , Medical , Legal , Financial , Acronyms , Wikipedia . island, relatively small body of land surrounded entirely by water. (As the oceans form a continuous mass of water on the earth's surface, all continents are islands in the strict sense of the word.) The largest islands on earth are, in descending order of size, Greenland Greenland, Green. Kalaallit Nunaat, Dan. Grønland, the largest island in the world (2005 est. pop.

56,000), 836,109 sq mi (2,166,086 sq km), self-governing overseas administrative division of Denmark, lying largely within the Arctic Circle. ..... Click the link for more information. , New Guinea New Guinea , island, c.342,000 sq mi (885,780 sq km), SW Pacific, N of Australia; the world's second largest island after Greenland. Politically it is divided into two sections: the Indonesian provinces of Papua and West Papua in the west and the independent country of Papua New ..... Click the link for more information. , Borneo Borneo , island (1990 pop. 9,102,906), c.287,000 sq mi (743,330 sq km), largest of the Malay Archipelago and third largest island in the world, SW of the Philippines and N of Java. ..... Click the link for more information. , Madagascar Madagascar , officially Republic of Madagascar, republic (2005 est. pop.

18,040,000), 226,658 sq mi (587,045 sq km), in the Indian Ocean, separated from E Africa by the Mozambique Channel. Madagascar is the world's fourth largest island. ..... Click the link for more information. , Baffin Island Baffin Island, 183,810 sq mi (476,068 sq km), c.1,000 mi (1,610 km) long and from 130 to 450 mi (210–720 km) wide, in the Arctic Ocean, Nunavut Territory, Canada. It is the fifth largest island in the world and the easternmost member of the Arctic Archipelago. ..... Click the link for more information. , Sumatra Sumatra , island (1990 pop.

36,471,731), c.183,000 sq mi (473,970 sq km), Indonesia, in the Indian Ocean along the equator, S and W of the Malay Peninsula (from which it is separated by the Strait of Malacca) and NW of Java (across the narrow Sunda Strait). ..... Click the link for more information. , Honshu Honshu , island (1990 pop. 98,352,000), c.89,000 sq mi (230,510 sq km), central Japan. It is c.800 mi (1,290 km) long and from c.30 to 150 mi (50–240 km) wide and is the largest and most important island of Japan. ..... Click the link for more information. (largest of the islands of Japan), and Great Britain Great Britain, officially United Kingdom of Great Britain and Northern Ireland, constitutional monarchy (2011 pop.

63,181,775), 94,226 sq mi (244,044 sq km), on the British Isles, off W Europe. The country is often referred to simply as Britain. ..... Click the link for more information. . Depending on their origin, islands are either continental or oceanic. Continental islands are created by rise in sea level where only the summits of coastal highlands remain above water; or by the sea breaking through an isthmus or peninsula and cutting the land from the mainland. Typical continental islands are Great Britain and Martha's Vineyard Martha's Vineyard , island (1990 est. pop. 8,900), c.100 sq mi (260 sq km), SE Mass., separated from the Elizabeth Islands and Cape Cod by Vineyard and Nantucket sounds. ..... Click the link for more information. . Other islands emerge along coasts as barrier islands, such as the Outer Banks Outer Banks or the Banks, chain of sand barrier islands and peninsulas, c.175 mi (280 km), along the Atlantic coast of SE Va. and E N.C.

Separated by inlets and enclosing several saltwater lagoons, or sounds, the main islands, from north to south, are Bodie, Roanoke, ..... Click the link for more information. , off North Carolina. Oceanic islands can result from volcanic islands rising above the water, especially on or near a mid-ocean ridge, as when the island of Surtsey Surtsey, volcanic island, c.1.25 sq mi (3.2 sq km), S of Iceland in Vestmannaeyjar (Westman Islands). The island was formed by the eruption (Nov., 1963) of Sutur, an underwater volcano named for a giant of Icelandic legend. For four months the fissure, estimated to be c. ..... Click the link for more information. appeared along the Mid-Atlantic Ridge S of Iceland in 1963. Island arcs, such as the Aleutian Islands Aleutian Islands , chain of rugged, volcanic islands curving c.1,200 mi (1,900 km) west from the tip of the Alaska Peninsula and approaching Russia's Komandorski Islands. ..... Click the link for more information.

, result from magmatic activity associated with the convergence of lithospheric plates (see plate tectonics plate tectonics, theory that unifies many of the features and characteristics of continental drift and seafloor spreading into a coherent model and has revolutionized geologists' understanding of continents, ocean basins, mountains, and earth history. ..... Click the link for more information. ). Oceanic islands may also be the emergent tips of volcanoes (seamounts) formed by hotspots. Oceanic islands that result from coral growth on the summit of seamounts are called coral islands or atolls (see coral reefs coral reefs, limestone formations produced by living organisms, found in shallow, tropical marine waters. In most reefs, the predominant organisms are stony corals, colonial cnidarians that secrete an exoskeleton of calcium carbonate (limestone). ..... Click the link for more information. ). These low islands only occur in tropical ocean areas. Oceanic islands are generally characterized by low faunal diversity, consisting of a few sea birds and insects. Vegetation is usually more abundant, as seeds are carried from remote lands by wind, water currents, and birds. What does it mean when you dream about an island?

To escape to an island in a dream may mean the peace of solitude is needed by the dreamer. A further meaning is that the dreamer is afraid of the surrounding waters of his or her unconscious and wishes to remain isolated from his or her inner feelings. island Iceland Quick & Fun Facts Iceland Quick & Fun Facts Iceland Quick & Fun Facts Iceland has the most active volcano area in the world, the largest waterfall and glacier in Europe, the northern most botanical garden and golf course in the world, the cleanest capital in the world, a population with the longest life expectancy and had the first democratically elected female president in the world, Mrs. Vigdis Finnbogadottir. And there is more… Iceland is one of the Nordic countries and part of Scandinavia (Denmark, Finland, Iceland, Norway, and Sweden). Reykjavík is the capital city of the Republic of Iceland. Hvannadalshnukur (2,119m) is the highest point in Iceland. Vatnajokull glacier in Southeast Iceland is Europe’s largest glacier. Hekla is Iceland's most active volcano; Hekla is also a common female name in Iceland.

In 1963 a new volcano appeared in the Atlantic close to Iceland. It grew to become an island now called Surtsey. The English word "geyser" comes from Iceland's Great Geysir in Haukadalur. The phenomenon of the Northern Lights (Aurora Borealis) can be seen during mid-winter (November-December) when the weather is clear. The "Althingi", the Icelandic parliament, dates back to the early tenth century. The last name of Icelanders is derived from their father's first name. In the telephone book everyone is listed by their first name. In the last quarter of the nineteenth century twenty percent of Iceland's population emigrated to Canada and the USA. In the 1960s and 70s there was a dispute between Iceland and the UK over fishing grounds, known as the "Cod Wars". The population of Iceland reached 300,000 in the year 2006. Soccer is Iceland’s favourite team game. Icelandic, the language, belongs to the Germanic language family that includes German, Dutch and all the Nordic languages except Finnish.

Its closest 'living relative' is Faroese - both are derived from Old Norse. Iceland, Not so quick (but still fun) facts! Supernatural Iceland Elves, trolls and ghosts Surveys show that despite their obsession with modern technology, as many as 80% of Icelanders believe in the existence of elves. Even today, roads have been rerouted and building plans redesigned or abandoned to avoid disturbing rocks where elves are said to live. All around the country, strange lava formations were once explained in folktales as trolls who were turned to stone when caught outdoors in daylight. But only children in Iceland believe in trolls today, and the once widespread belief in ghosts is in decline, some say because electricity has taken the fright out of the long winter nights. A different kind of fauna Contrary to what many people think, there are no polar bears in Iceland. Admittedly, every ten years or so a polar bear may arrive as an accidental tourist on an ice flow from Greenland, However, they aren't invited to stay. The Arctic fox is the only native mammal. Reindeer live in the wild in east Iceland, but were only imported in the 18th century.

Mink have also adapted to the wild, the descendants of animals which escaped from fur farms in the 1930s. A number of pedigree animal stocks are only found in Iceland. Many of these rare breeds have disappeared elsewhere and are the original decedents brought over by the Vikings, including the Icelandic horse, cow, sheep and sheepdog. Marine mammals are also found in abundance along the coasts, especially minke whale, humpback whale, fin whale and several species of seals. Some whale watching tour operators claim 98% success rates for sightings. Vikings in America Leif the Lucky, discoverer of America Five hundred years before Columbus, the first European set foot in America: Leif the Lucky, who was born in west Iceland, the son of Erik the Red. According to the Sagas, Leif wintered in a place he named Vinland after grapes he found growing there, around the year 1000. A likely site is Newfoundland, where ruins of a Viking farmstead have been excavated.

Leif left the New World but another expedition was led there by Thorfinn Karlsefni and his wife Gudrid Thorbjarnardottir, who explored as far as where New York stands today and spent three or four years trying to establish a settlement before they gave up the idea. While in America they had a son, Snorri Thorfinnsson, the first European born in the New World. Gudrid and Thorfinn left America to live on a farm in north Iceland, Glaumbær, and when she was widowed she made a pilgrimage on foot to Rome, becoming the first known female transatlantic traveller and undoubtedly the most widely travelled women for at least the next 500 years. Treeless Iceland Why aren’t there any trees in Iceland? Ancient Icelandic writings from the 12th century tell how the settlers three centuries earlier found a country that was covered with trees from mountain to shore. The fact that they mention this point suggests that trees were already becoming scarcer then. Over the centuries they were chopped down for timber and firewood, while grazing sheep, harsh winters and ash from volcanic eruptions caused erosion that prevented trees from taking root.

Reforestation work began early this century and although there is still only one proper forest in the country (Hallormstadaskógur in the east), Iceland today plants more trees per head of population than any other nation in the world (around four million a year, or 16 for every man, woman and child.) Traditional food Get your teeth into tradition Most visitors are full of praises for Iceland's ocean-fresh seafood and mouth-watering mountain lamb, but these are only part of the local culinary experience. Traditional food is also served, made using the only preservation methods available when people had to store up for the winter in the days before refrigerators. Some is delicious, some is different, and is very good to boast about to your friends after you've finished it. Meat was commonly smoked, and the delicious hangikjöt (smoked lamb) is still popular today. Among dairy products, a big favourite with visitors is skyr (curds), especially served with fresh bilberries in late summer. On the more adventurous side is slátur, which literally means "slaughter" but is like haggis.

And for those with nerves of steel and stomachs of iron, the menu for the Thorri midwinter feast (January/February) is a real challenge. Delicacies there include some quite indelicate cuts of meat, including boiled sheep's head (on the bone or pressed), ram's testicles pickled in whey, and loin bags. But what really sorts the men out from the boys is rotten shark, cured by burying, washed down with a well-deserved shot of Black Death schnapps. Hint for beginners: if you manage to get it past your nose, you're half way there. Ice and fire Glaciers and volcanoes side by side Contrasting forces of ice and fire exist side by side in Iceland. Some 11% of the country’s surface is covered with glaciers and about 30% is lava fields. On average, a volcano erupts every five years, but fortunately only rarely where anyone lives. Vatnajökull glacier, measuring 8,400 km=, is the largest ice cap in Europe in fact it is larger than all the other glaciers in Europe combined. But rather like the character of the Icelanders themselves, there is fire beneath the icy surface.

In 1996 and 1998, volcanoes erupted under the ice of Vatnajökull, pushing up new mountains and causing huge melt water floods along the uninhabited south coast. Land still taking shape The youngest country in the world Geologically speaking, Iceland is hardly out of playschool, since it only began to rise from the North Atlantic seabed about 25 million years ago, the product of volcanic eruptions that are still going on today. Parts of the country are still so rugged that American astronauts chose Iceland as a training ground to prepare them for landing on the moon. And Iceland is still taking shape before peoples eyes: the newest land is Surtsey, an island which rose from the sea during an underwater eruption off the south coast in 1963. European or American Is Iceland in Europe or America? Iceland lies on the Mid-Atlantic Ridge, the mainly underwater border where the tectonic plates of America and Eurasia are slowly spreading apart. A huge rift runs through the country from southwest to northeast, disappearing and surfacing by turns, where the plates are heading in different directions.

So although Iceland is geographically and culturally part of Europe, half of it lies on the American plate, and is moving westwards at an estimated 1-2 cm a year. At the ancient parliament site of Thingvellir, which lies on this rift, you can stand on the edge of America (geologically speaking) and see all the way to Europe, 10 km away. Ancient Viking language On speaking terms with the Vikings The Vikings who settled Iceland in the ninth and tenth centuries brought with them their language which has remained basically unchanged ever since. Literacy has been widespread ever since the first sagas were written down in the thirteenth century, and people today can still read them without difficulty. Unlike most western cultures, there are no real dialects and the best language tends to be spoken in the countryside rather than the big city. One strange feature of Icelandic is that it refuses to accept foreign words, but almost always coins new words from ancient Viking roots for even the most complex technological concepts. A classic example is the word for computer: tölva, a hybrid formed from old words for number and prophetess.

Icelandic names A nation of sons and daughters Everyone in Iceland is on a first name basis, and people are even listed by first name in the telephone directory. Most Icelanders still use the old Viking patronymics instead of family surnames, with different forms for sons and daughters. For example, a man called Haraldur Magnusson and his wife Helga Jonsdottir might have a son called Petur whose final name would then be Haraldsson, and a daughter called Ingibjörg Haraldsdottir. Logical enough, but the naming system sometimes raises eyebrows at passport control and hotel reception desks when Icelanders travel abroad. In the age of women’s lib, increasing numbers of children are being given matronymics, i.e. identified as the son or daughter of their mother rather than their father. Leisure & sports Midnight golf and swimming in blizzards Offbeat sporting attractions have become a must for visitors to Iceland.

The top favourites include swimming in a geothermal hot spring (where people can bath in warm open-air pools all year round – even during blizzards!), a trek on the small but hardy Icelandic horse (the most natural way to travel through nature as it has been for more than a thousand years), and salmon & trout fishing. During the midsummer nights, the annual Arctic Open golf tournament in Akureyri attracts players from around the world with its midnight tee time during the midnight sun. Action sports are the latest fad, including snowmobiling on glaciers and river rafting on some of the most hair-raising glacial rivers this side of Hollywood. Volcanic Islands | Article about Volcanic Islands by The Free Dictionary Volcanic Islands | Article about Volcanic Islands by The Free Dictionary Related to Volcanic Islands: oceanic island island, relatively small body of land surrounded entirely by water. (As the oceans form a continuous mass of water on the earth's surface, all continents are islands in the strict sense of the word.) The largest islands on earth are, in descending order of size, Greenland Greenland, Green. Kalaallit Nunaat, Dan.

Grønland, the largest island in the world (2005 est. pop. 56,000), 836,109 sq mi (2,166,086 sq km), self-governing overseas administrative division of Denmark, lying largely within the Arctic Circle. ..... Click the link for more information. , New Guinea New Guinea , island, c.342,000 sq mi (885,780 sq km), SW Pacific, N of Australia; the world's second largest island after Greenland. Politically it is divided into two sections: the Indonesian provinces of Papua and West Papua in the west and the independent country of Papua New ..... Click the link for more information. , Borneo Borneo , island (1990 pop. 9,102,906), c.287,000 sq mi (743,330 sq km), largest of the Malay Archipelago and third largest island in the world, SW of the Philippines and N of Java. ..... Click the link for more information. , Madagascar Madagascar , officially Republic of Madagascar, republic (2005 est. pop.

18,040,000), 226,658 sq mi (587,045 sq km), in the Indian Ocean, separated from E Africa by the Mozambique Channel. Madagascar is the world's fourth largest island. ..... Click the link for more information. , Baffin Island Baffin Island, 183,810 sq mi (476,068 sq km), c.1,000 mi (1,610 km) long and from 130 to 450 mi (210–720 km) wide, in the Arctic Ocean, Nunavut Territory, Canada. It is the fifth largest island in the world and the easternmost member of the Arctic Archipelago. ..... Click the link for more information. , Sumatra Sumatra , island (1990 pop.

36,471,731), c.183,000 sq mi (473,970 sq km), Indonesia, in the Indian Ocean along the equator, S and W of the Malay Peninsula (from which it is separated by the Strait of Malacca) and NW of Java (across the narrow Sunda Strait). ..... Click the link for more information. , Honshu Honshu , island (1990 pop. 98,352,000), c.89,000 sq mi (230,510 sq km), central Japan. It is c.800 mi (1,290 km) long and from c.30 to 150 mi (50–240 km) wide and is the largest and most important island of Japan. ..... Click the link for more information. (largest of the islands of Japan), and Great Britain Great Britain, officially United Kingdom of Great Britain and Northern Ireland, constitutional monarchy (2011 pop.

63,181,775), 94,226 sq mi (244,044 sq km), on the British Isles, off W Europe. The country is often referred to simply as Britain. ..... Click the link for more information. . Depending on their origin, islands are either continental or oceanic. Continental islands are created by rise in sea level where only the summits of coastal highlands remain above water; or by the sea breaking through an isthmus or peninsula and cutting the land from the mainland. Typical continental islands are Great Britain and Martha's Vineyard Martha's Vineyard , island (1990 est. pop. 8,900), c.100 sq mi (260 sq km), SE Mass., separated from the Elizabeth Islands and Cape Cod by Vineyard and Nantucket sounds. ..... Click the link for more information. . Other islands emerge along coasts as barrier islands, such as the Outer Banks Outer Banks or the Banks, chain of sand barrier islands and peninsulas, c.175 mi (280 km), along the Atlantic coast of SE Va. and E N.C.

Separated by inlets and enclosing several saltwater lagoons, or sounds, the main islands, from north to south, are Bodie, Roanoke, ..... Click the link for more information. , off North Carolina. Oceanic islands can result from volcanic islands rising above the water, especially on or near a mid-ocean ridge, as when the island of Surtsey Surtsey, volcanic island, c.1.25 sq mi (3.2 sq km), S of Iceland in Vestmannaeyjar (Westman Islands). The island was formed by the eruption (Nov., 1963) of Sutur, an underwater volcano named for a giant of Icelandic legend. For four months the fissure, estimated to be c. ..... Click the link for more information. appeared along the Mid-Atlantic Ridge S of Iceland in 1963. Island arcs, such as the Aleutian Islands Aleutian Islands , chain of rugged, volcanic islands curving c.1,200 mi (1,900 km) west from the tip of the Alaska Peninsula and approaching Russia's Komandorski Islands. ..... Click the link for more information.

, result from magmatic activity associated with the convergence of lithospheric plates (see plate tectonics plate tectonics, theory that unifies many of the features and characteristics of continental drift and seafloor spreading into a coherent model and has revolutionized geologists' understanding of continents, ocean basins, mountains, and earth history. ..... Click the link for more information. ). Oceanic islands may also be the emergent tips of volcanoes (seamounts) formed by hotspots. Oceanic islands that result from coral growth on the summit of seamounts are called coral islands or atolls (see coral reefs coral reefs, limestone formations produced by living organisms, found in shallow, tropical marine waters. In most reefs, the predominant organisms are stony corals, colonial cnidarians that secrete an exoskeleton of calcium carbonate (limestone). ..... Click the link for more information. ). These low islands only occur in tropical ocean areas. Oceanic islands are generally characterized by low faunal diversity, consisting of a few sea birds and insects. Vegetation is usually more abundant, as seeds are carried from remote lands by wind, water currents, and birds. What does it mean when you dream about an island?

To escape to an island in a dream may mean the peace of solitude is needed by the dreamer. A further meaning is that the dreamer is afraid of the surrounding waters of his or her unconscious and wishes to remain isolated from his or her inner feelings. island Volcanoes Volcanoes Nature & Environment Volcanoes Iceland sits astride the middle of the Mid-Atlantic Ridge, which is an integral part of the global mid-oceanic ridge system. This ridge is a 40.000 km crack in the ocean floor caused by the separation of the North American and Eurasian tectonic plates. The Mid-Atlantic Ridge has made Iceland into a landmass between the submarine Reykjanes Ridge to the southwest and the Kolbeinsey Ridge to the north, and has been active during the last 20-25 million years, broadly coinciding with the time-span of active volcanism in Iceland. Accordingly, the western part of Iceland, to the west of the volcanic zones, belongs to the North American plate and the eastern part to the Eurasian plate.

Where plates meet, they can rub against each other as they slide in opposite directions; they can collide head-on in a stalemate, pushing each other up or down like two fighting rams; or one might win out and push the other one beneath it. Sometimes, they only move away from each other, releasing pressure and exposing the lava sea between them. This allows the lava to stream to the surface, where it cools down and forms new land. When this happens, the area of separation is called a "constructive junction," and this is precisely what is happening in Iceland. Volcanic eruptions and earthquakes follow each other. Parts of Iceland are frequently shaken by earth tremors. Catastrophic earthquakes occur at longer intervals than the volcanic eruptions. Some of the worst earthquakes devastated large areas of southern Iceland in 1784 and 1896. There are over a hundred volcanos on the central plateau which have not erupted in the past thousand years and between 30 and 40 that areactive, meaning that they have erupted within last few centuries. On average, Iceland experiences a major volcanic event once every 5 years.

Since the Middle Ages, a third of all the lava that has covered the earth's surface has erupted in Iceland. However, according to a recent geological hypothesis, this estimate does not include submarine eruptions, which are much more extensive than those on the land surface. The most famous and active volcano in Iceland is mount Hekla, which has erupted 18 times since 1104, the last time in 2000. Other active volcanos, measured in terms of the number of eruptions besides Hekla, are Grímsvötn, Katla, Askja and Krafla. Katla, has erupted about 20 times since the settlement of Iceland. A volcano in Heimaey in the Vestmannaeyjar Islands off the south coast, which was thought to be long extinct as it had not been active for about 5,000 years, suddenly erupted in 1973. Heimaey is the largest of the Vestmanneyjar Islands, and the only one that is inhabited.

The fishing town of Heimaey, with a population of 5,300, was only 200-300 m away from the eruption, which began without warning in the volcano Eldfell during the night of 23 January Nearly all the inhabitants were evacuated to the mainland by fishing boats and aircraft during the first night. Only a few hundred people stayed behind to carry out necessary work. The eruption lasted 5 months and the village was nearly destroyed by lava, ash and fire. Miraculously, two-thirds of Heimaey was saved by using barriers and huge jets of water to cool the lava, which in turn created a rock damn against the flow. Ironically, by the time the eruption was over, the town's harbour was even better than before - the new land provided greater protection from wind and water. After the end of the eruption, people started to move back and the population is now about 4,900. A typical submarine eruption occurred on the Reykjanes Ridge in 1963, resulting in a new island, Surtsey, which forms part of the same archipelago as Heimaey.

It emerged from a depth of 130 m during an eruption which lasted until 1967. At its largest, this new island had an area of 2.8 km², but has now been reduced reduce by wave action to 1,5 km². At numerous times in Iceland's history, volcanos have meant disaster. The largest recorded lava flow in world history occurred here in the summer of 1783, when a 25-km crater row, Lakagigar, southwest of Vatnajökull, poured out 14 km3 of lava, the greatest lava flow witnessed on Earth, at least in the last millennium. So much ash was released that the sun was obscured for a time, and hundreds of thousands of sheep and cattle perished from the poisonous gases. The ensuing famine led to the death of 20% of the population, or about 10,000 people. The lava-field created by the eruption covered 580 km², with a total volume of 12 km³. During the summer of 1783, a bluish haze from the eruption covered Europe and Western Asia, causing difficulties in agriculture there.

This was one of the reasons for the 1789 revolt in France. The same geological activity that creates the volcanos provides an endless supply of geothermal energy. Over 90% of housing in Iceland I is heated by natural geothermal heat - one of the cheapest and cleanest forms of energy in existence. Hot springs can be found almost everywhere, and the melt water created by sub-glacial volcanos provides the country with a huge potential source of of hydroelectric power. All this clean energy has made Iceland one of the least polluted countries in the world.

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 plates and notable volcanoes.

Most volcanoes (notable ones indicated by red triangles) occur in areas where tectonic plates meet (indicated by purple lines). Grolier Geologists measure the temperature of rocks in a volcanic field using a thermocouple thermometer. Grolier In late 2004, a slumbering giant began to stir. For the first time since 1986, Mount St. Helens, in Washington State, rumbled back to life. The most infamous volcano in the United States shook with small earthquakes as a lava dome grew in its crater and great bursts of steam shot skyward. For scientists, state officials, and local residents, this activity served as a reminder of the volcano's destructive potential. Back in 1980, Mount St. Helens released its pent-up fury with the force of a 400-megaton nuclear bomb. From the mountain's north side came a blast of superhot gas and ash that destroyed everything in an 18-mile (29-kilometer) path. A different kind of problematic eruption occurred in Iceland in 2010, when a volcano awoke from beneath a glacier after 187 years of silence.

The ash cloud from the eruption of Eyjafjallajökull (pronounced AY-ya-fYAT-la-YOH-gut) forced airports across Europe to close for days, snarling air traffic and stranding thousands of travelers. The airline industry reported a loss of at least $1.7 billion due to flight cancellations. Even a small amount of ash can damage aircraft engines, perhaps causing them to seize up. Eyjafjallajökull produced a voluminous cloud of ash. Its fiery magma flowed onto glacial ice and rapidly cooled into fine particulates and steam that billowed upward for 5 miles (8 kilometers) and were carried away by the prevailing winds. The volcano is well named: Eyja is Icelandic for "island"; Fjalla means "mountain"; and Jokull is "glacier." The human fascination with volcanoes can hardly be tamed. In Hawaii, volcanic eruptions are still treated like Fourth of July fireworks—drawing hundreds of thousands of tourists each year. Fortunately, the ongoing eruptions from the Hawaiian Islands' many volcanoes are generally mild. The activities of volcanoes can be ranked with earthquakes as among the most impressive manifestations of the restless forces that shape our planet.

Rivers of molten rock erupt from Earth's surface, accompanied by fiery ashes, rock fragments, and clouds of gas. Such volcanic processes have covered vast areas of land with their molten flow—just as the flow from undersea volcanoes continuously builds new ocean floor. WHAT ARE VOLCANOES? A volcano is a vent or fissure in Earth's crust. At intervals, hot solids, liquids, and gases emerge more or less violently from it. The materials that issue from the vent eventually build up a mountainous cone. The term "volcano" is often applied, not only to the vent, but to the mountain itself. Volcanic mountains are generally conical in shape, and often very lofty. The top of a typical volcano shows a usually cup-shaped or basin-shaped depression. This depression is known as the crater. Within the crater is the volcanic neck, a pipe or funnel through which lava, gas, and ash continue to travel up through the center of the cone. The sides of the cone may develop side vents, from which hot material can also flow out of the volcano.

The angle, or steepness, of the volcanic cone depends on the viscosity, or thickness, of the lava and the cohesiveness, or stickiness, of the material that has been thrown out. The more viscous the lava and the more cohesive the ejected material, the steeper the cone. The steep volcanoes on Réunion Island, in the Indian Ocean, are formed from such very viscous lava. By contrast, the volcanoes of the Hawaiian Islands are gradual in slope, built up by very fluid lava. Some volcanic cones are made up of cindery and slaglike fragments, others of sheets of lava, and still others of a mixture of both. The more massive volcanoes are usually built up out of alternating layers of lava sheets, rock fragments, and volcanic dust. Mountains that arise through volcanism can be reshaped and broken apart by the same forces. Explosions may tear away part of the summit, as they did on Mount St. Helens. Such eruptions have, over the centuries, changed the shape of Italy's Mount Vesuvius many times. When volcanoes develop side vents, these may give rise to subsidiary, or "parasitic," cones, which greatly alter the original conical shape.

The volcanoes of the Hawaiian Islands have thousands of subsidiary cones of this type. TYPES OF VOLCANOES Volcanoes occur in a variety of sizes and shapes. Some are small domes of lava or ash that rise less than 100 feet (30 meters) above sea level, while others are great mountains, rising several thousand feet. The type of magma ejected from the volcano determines the volcano's appearance and structure. Very fluid magma flows rapidly and spreads over great distances, forming shield volcanoes—the largest type of volcano. Shield volcanoes are dome-shaped mountains with broad bases and gently sloping sides. The volcanoes of Hawaii and Iceland are examples of this type. Thicker magma with a higher gas content usually erupts violently. Volcanic fragments are blown high into the air, and land near the vent, forming steep-sided cinder cones that rise only a few hundred feet above the surrounding terrain. Cinder cones, such as Mexico's Paricutín, are the most common type of volcano. Composite volcanoes are formed by periods of quiet eruptions of fluid magma followed by violent eruptions of viscous, gas-rich magma. These cyclical eruptions result in the formation of a steep-sided, conical volcano. Mount St.

Helens and Mount Vesuvius are typical composite volcanoes. Calderas. The name "caldera," meaning "caldron" in Spanish, has been given to volcanoes with very broad and comparatively shallow craters. A caldera results from the explosion and partial collapse of the volcano summit. Among the most impressive calderas in the world is Kilauea, part of the large Mauna Loa Volcano on the island of Hawaii. Kilauea's crater is about 2 miles (3 kilometers) wide. Many dormant calderas eventually fill with water to form mountaintop lakes. Among the most beautiful is Crater Lake in southwestern Oregon. This nearly circular lake is surrounded by rock walls that range in height from 885 to 2,200 feet (270 to 670 meters). In some places, the lake is 2,000 feet (600 meters) deep. The Indians called it "Sea of Silence." Mud volcanoes. Sometimes gas issuing from a volcanic vent blows out a great quantity of sand and clay. This material forms the volcanic cone, which heavy rains then turn to mud.

After the mud hardens into a surface layer, gas may accumulate beneath it with increasing pressure. Eventually the gas blows off the top layer of the cone. Such mud volcanoes are frequently found in oil and gas fields. Some arise in regions where volcanic steam escapes through mud. On November 13, 1985, lava and steam from the Nevado del Ruiz Volcano in Colombia caused mudflows that buried more than 23,000 people. Plug domes. In some cases, lava coming out of a volcanic vent is too viscous to flow—because it has either cooled or lost much of its gas content. As a result, hardening lava piles up in a great mound over the vent. Such plug domes can be seen in Lassen Volcanic National Park in California. An unusual type of plug dome appeared on Mount Pelée in Martinique after the disastrous eruption of 1902. The lava that filled the vent after the eruption hardened into rock at the surface. The interior was highly viscous, however, and raised the entire plug into a tower some 1,000 feet (300 meters) in height above the summit of the volcano.

Gradually it crumbled away, largely as the result of internal gas explosions. Fissures. Not all molten material ejected from the ground is piled up into mountains. In many instances, the lava seeps from a large crack, or fissure, and spreads more or less evenly over large areas. Such outpourings are called fissure eruptions, or plateau flows. The lava that issues from a fissure eruption is not very viscous. An example of a vast fissure can be found in the Deccan region of western India. There, lava has covered an area of more than 200,000 square miles (520,000 square kilometers). Fissures are especially common in Iceland. In 1783, observers watched two streams of lava issue from a fissure there, and flow for many miles. Iceland's lava desert of Odadahraun, which covers an area of more than 1,350 square miles (3,500 square kilometers), is also a product of fissure eruptions. Submarine volcanoes. The underwater volcanoes of the world are among the most spectacular of all.

Mount Etna and many other volcanoes had their birth under the sea. Nobody knows how many active volcanoes are now at work in the ocean depths. Often they throw up cinders and steam and agitate the surface of the sea. Vast outpourings of lava on the ocean floor accompany these eruptions. Sometimes layer upon layer of lava is formed, and at last an island appears above the ocean surface. The volcanic chain of the Hawaiian Islands was created in this way. Occasionally submarine volcanoes betray their presence by very suddenly thrusting a new island into view or destroying an old island, which then sinks into the sea. The Mediterranean Sea has often witnessed the sudden appearance and disappearance of volcanic islands. In 1831, a new volcanic islet called Graham Island suddenly appeared between Sicily and Africa. This island reached a height of some 200 feet (60 meters), and attained a circumference of some 3 miles (5 kilometers). However, since it was composed of loose materials, it was rapidly eroded by the waves, and, in a few brief months, it was reduced to a shoal called Graham's Reef. Other islands created by submarine volcanoes develop into more permanent landforms.

An island in the Bering Sea called Bogoslof Island appeared about 40 miles (65 kilometers) west of Unalaska Island in 1796, following such an underwater eruption. In 1963, a volcanic island, later named Surtsey, appeared off Iceland's southwest coast near the Vestmannaeyjar Islands. WHERE VOLCANOES ERUPT AND WHY There are several thousand volcanoes around the world, and between 50 and 60 erupt every year. Most lie in the Pacific, nearly half in the western Pacific alone. The world's volcanoes are distributed in a series of belts, the largest being the "Ring of Fire"—a necklace of volcanoes that rims the Pacific Ocean. Other belts run through Italy and Indonesia. The Ring of Fire begins along the Aleutian Islands off the coast of Siberia and continues along the west coast of Alaska. Many active volcanoes can be found there. The ring then turns south and extends into the Cascade Range of Canada and the United States, whose volcanoes have been silent since 1914, with the notable exception of Mount St. Helens.

The ring continues down the west coast, through Baja California, western Central America, and the Andes Mountains of South America. A chain of South American volcanoes begins with the Nevado del Tolima, in Colombia, and continues down to Corcovado Volcano, in southern Chile. This chain includes Ecuador's Cotopaxi. At a height of 19,500 feet (5,900 meters), it is the highest active volcano on land. The western side of the Ring of Fire swings from the Bering Strait to the west side of the Pacific Ocean and then runs down to the Indian Ocean. The islands of Japan are a long volcanic mountain chain lifted above the ocean. This string of volcanoes passes through the Philippines, the Moluccas, and the Sunda Islands to New Guinea. Another belt of volcanoes, in the Atlantic Ocean, also includes a considerable number of volcanic islands. Among them are West Spitsbergen, Jan Mayen Island, Iceland, the Azores, Madeira, the Canary Islands, and the Cape Verde Islands. Still another volcanic belt extends southward from Saudi Arabia. It takes in the Red Sea, Ethiopia, and Madagascar. Why do these belts occur where they do?

They tend to arise over areas where Earth's crust is under great stress. Specifically, they occur where one crustal plate is colliding with and diving under another or where crustal plates are spreading apart. The collision of crustal plates generates tremendous heat that melts some of the rock along the diving, or subducting, plate. This melted rock, or magma, can then force its way up to the surface with explosive force. When plates spread apart, magma pushes up between the plates. This type of volcanic activity occurs along the Mid-Atlantic Ridge, an undersea mountain range stretching the length of the Atlantic Ocean. Iceland's volcanoes are found along this volcanic ridge. Outside of these volcanic belts, volcanoes occur in isolated spots around the world. These hot spots do not always occur over colliding crustal plates, as do volcanic belts. In fact, they seem to arise from points deep beneath Earth's crust. Over time, as crustal plates slowly move over these hot spots, a series of volcanoes may appear, forming a trail. The Hawaiian Islands were created by this process. Predicting Eruptions. Volcanoes vary greatly in activity. As a rule, periods of partial or complete inactivity alternate with periods of explosive violence.

Until the eruption of A.D. 79, Vesuvius had been in repose for centuries. In 2005, British researchers warned that Vesuvius was a major threat to the people of Europe. Though the volcano has been quiet since the 1940s, another big eruption could claim thousands of lives. Other volcanoes are constantly active. Stromboli, a volcanic island off Italy's Lipari Islands, has been pouring forth lava for more than 2,000 years. Volcanoes of this type have relatively subdued eruptions. Most of the world's volcanoes are entirely, or presumably, extinct. Among these are the great volcano of Palma, in the Canary Islands; Mount Shasta, in California; Mount Hood, in Oregon; and Mount Rainier, in Washington. The peaks of some of these are snowcapped. Their slopes have been eroded to such an extent that they are fast losing their characteristic shape. In some instances, the forces of erosion have worn down extinct volcanoes almost to their foundations. Just when a dormant volcano will reawaken is, understandably, of great interest. Many volcanic eruptions are preceded by days, weeks, or even months of local earthquake activity.

This may be accompanied by loud rumblings that may be due to the movement of underground gases under great pressure. In late 2004, after more than a decade of relative inactivity, Mount St. Helens again came to life, triggering local earthquakes and later emitting steam and lava. Hot springs may suddenly appear around a volcano that is ready to erupt. Or the water level of a nearby lake may suddenly and dramatically rise or fall. Yet another clear warning sign is an unusual melting of snow from the volcanic mountain's summit. The actual tilting or bulging of ground around a volcano is an unmistakable clue that an eruption threatens. It is usually caused by the underground movement and buildup of magma. Today scientists are trying to better understand volcanic activity so that they can set early-warning systems in place. They do so with a variety of sophisticated devices placed around a volcano. These include seismometers, which can detect slight earthquake movements, and tiltmeters, which can pick up slight swellings within the volcano. Magnetometers detect the local distortions in Earth's magnetic field caused by magma rising in volcanic vents. With sufficient warning, workers can build channels and barriers to divert some of a volcano's destructive lava away from inhabited areas.

At the least, inhabitants can be evacuated in time. ANATOMY OF AN ERUPTION The start of an actual volcanic eruption is signaled by the release of an enormous quantity of superheated gases. As these gases rush out of the crater, they usually carry vast quantities of rocks, ashes, lava, and other materials. The ground may shake violently, accompanied by a tremendous roar. It is said that the roar that accompanied the 1815 eruption of Tambora, a volcano on Sumbawa Island in Indonesia, could be heard 950 miles (1,500 kilometers) away! The column of gases and particles issuing from a volcano can reach great heights. When it does, friction between the particles creates static electricity, which discharges as forked lightning and thunder. Often the gaseous column is so thick that it hides the Sun and may create darkness for days. By far the greatest part of the gases that issue from volcanic vents is made up of steam—superheated water vapor, which may attain a temperature of more than 900° F (580° C). The steam's condensation may cause torrential rain. Some volcanoes also give off various sulfur compounds.

Kilauea in Hawaii, for example, has been emitting some 1,000 tons of sulfur dioxide a day since 1986! Other gases may include hydrogen chloride, carbon dioxide, carbon monoxide, methane, hydrogen, oxygen, and argon, all at high temperatures. Such gases can be deadly. In 1986, a cloud of volcanic gases erupted from Nios, a crater lake located in the Central African country of Cameroon, burning and suffocating 1,700 people and thousands of animals in a nearby village. Scientists now believe that the gas spewed out of the water after an underwater landslide or rainfall had stirred the lake. Volcanic gases are emitted, not only from the vent itself, but also from lava flows. These flows may continue to emit gases for weeks or months after the eruption has stopped. Lava Flow. Lava may be the most characteristic product of a volcanic eruption. In some cases, as in the great eruption of Mount Pelée in 1902, no lava at all is ejected. As a rule, however, after the volcano has "cleared its throat" with the discharge of superheated steam and other gases, lava begins to flow.

Usually the lava pours over the edges of the crater or from fissures in the sides of the volcano. Where there are a great many fissures, the volcano seems to "sweat" lava from numerous pores. The lava's rate of flow is often rapid at first, varying with the viscosity of the lava and the slope of the land. When the lava reaches a steep downward slope, it pours tumultuously over it. On gentle slopes, it may move very slowly. As the lava cools, its flow becomes much more sluggish. When it first issues from a crater, lava is red-hot or even white-hot, and it cools only very slowly. Consequently, even after a crust has formed and the lava has become cool enough to be walked on, it may still be red-hot below the surface. The surface appearance of cooled lava depends in part on its chemical composition. Very fluid lava flows tend to break up into many rough blocks as they cool. This type of block lava may ultimately pile up in tremendous heaps or mounds. When such a flow finally stops, the result is an exceedingly irregular formation—an accumulation of sharp-edged blocks and jagged fragments.

More-fluid lava flows cool and harden into a twisted, ropy structure with a multicolored, satiny surface. The Hawaiian word pahoehoe is used to describe it. Volcanic Rocks. In addition to lava, volcanoes discharge huge quantities of rocks, stones, cinders, and ashes. During its 1779 eruption, mighty Vesuvius hurled cinders to heights exceeding 10,000 feet (3,000 meters). In 1815, Tambora, on the Indonesian island of Sumbawa, covered the sea for many miles with such huge quantities of pumice stone and other debris that ship traffic could hardly force its way through them. Cotopaxi, a volcano in north-central Ecuador, is said to have flung a 220-ton block 9 miles (14.5 kilometers)! The accumulation of lava, rocks, and sand in the vicinity of a crater may reach amazing proportions.

The creation of the volcano known as Paricutín offers a striking example: On February 20, 1943, an earthquake signaled the appearance of a crater in a flat cornfield some 180 miles (290 kilometers) west of Mexico City. The crater began to belch forth rocks, sand, and immense streams of lava. The accumulation of materials around the crater mounted with fantastic speed. In less than a year, the newborn volcano Paricutín attained a height almost one-third that of Vesuvius, which had been many thousands of years in the making. Volcanic Ash and Steam. Sometimes volcanoes erupt with such tremendous force that most of the magma is blasted into tiny particles of dust and ash. This was the case with the mighty eruption of the Philippines' Mount Pinatubo in 1991. Ten miles (16 kilometers) away, tons of ash nearly buried the U.S. Air Force's Clark Air Base. In 1980, the ash emitted from Mount St. Helens did far more damage than any other material. In 2005, Mexico's Colima volcano violently hurled lava into the air and coated nearby villages in ash, forcing local residents to evacuate.

Occasionally, intensely hot ash accompanies other fragments and searing gases to form deadly pyroclastic flows. A pyroclastic flow usually consists of two parts: a basal flow of larger, heavier debris that hugs the ground as it rapidly hurtles down the volcano's slope, and a dense, roiling cloud of burning ash that rises above it. The extreme temperatures of ash, rocks, and gases, combined with the flow's speed of more than 50 miles (80 kilometers) per hour, can result in the explosive destruction of buildings, farmland, and forests, and death to humans and animals. The dust and ash from a large eruption can reach into the upper atmosphere, where it can affect weather around the world. Mount Pinatubo, for example, exerted a global cooling effect for years. The steam rising from even small active volcanoes results in the addition of considerable quantities of water to the atmosphere. This steam is believed to come partly from deep groundwater that has been superheated by surrounding magma. Also, the melting rock itself liberates a tremendous amount of steam. It is estimated that a single eruption of Mount Etna produced nearly 600 million gallons (2.28 billion liters) of water as steam.

The deluge of water from the condensed steam of an eruption often converts the volcanic dust into a sticky mud that overwhelms and buries everything in its path. The ancient Roman city of Herculaneum was buried during the eruption of Vesuvius in A.D. 79 by such an inundation of mud. The great eruption of Cotopaxi in 1877 covered many villages and entire forests with a deposit of mud mixed with lava and various kinds of debris. December 15, 2016

Question: What was the name of the island off Iceland which appeared in 1963 as a result of an underwater volcano?
Answer: Surtsey